Earth working and construction type machines, such as motor graders, excavators, wheel loaders, agricultural tractors, dozers and other similar machines, each include a cabin from which an operator controls movement of the machine and its associated work tools. The cabin shields the operator from harsh environmental conditions, and also protects the operator from injury in case of machine rollover. In order for the operator to be effective and efficient in controlling the machine, the operator should be provided with unobstructed views of critical areas surrounding the machine. These areas can include forward-located tool movement zones, side-located wheel (or track) locations, and rear quarter locations where machine collisions can occur.
A typical machine cabin is formed from a floor, a roof, and upright posts that extend between the floor and the roof. The posts are classified into one of three categories, depending on their location and function within the cabin. Specifically, a cabin typically includes A-posts, B-posts, and C-posts. A-posts are generally located at the front corners of the operator cabin, while C-posts are located at the rear corners of the cabin. A windshield is mounted between the A-posts, and a back wall and/or rear window is mounted between the C-posts. B-posts are located between the A-posts and the C-posts (i.e., at the sides of the cabin) and are used for mounting doors of the cabin.
An exemplary machine cabin is disclosed in U.S. Pat. No. 6,543,840 that issued to Colliar on Apr. 8, 2003 (“the '840 patent”). In the '840 patent, an attempt is made to improve operator visibility from within the cabin by eliminating the B-posts described above. In addition, the C-posts are curved outward towards sides of the cabin at an upper portion near the roof, so as to pass over wheel wells of the associated machine. This configuration allows the C-posts to support a rear window in a more compact configuration.
Although the machine cabin of the '840 patent may improve visibility in small-machine applications, it may still be less than optimal. In particular, the machine cabin of the '840 patent may not be suitable for large-machine applications, where B-posts are required for structural strength and rigidity. Further, the A- and C-posts, being located at corners of the machine cabin, may inhibit the operator from effectively viewing the tool movement zones and the rear quarter locations discussed above. Further, the structure of the machine cabin disclosed in the '840 patent may make packaging of associated electrical wiring and HVAC conduits difficult.
The disclosed machine cabin is directed to overcoming one or more of the problems set forth above and/or other problems of the prior art.